Hi,
I have a pair of MLTLs (Dayton RS225 + SB29RDNC) active powered by T-amps of a miniDSP.

They are the first DIY pair of speakers I've made and love how they sound -in fact I don't have nothing more on hand to compare then with-, but I have been recently reading here about FAST and I would like to try the concept in a low budget way (let's say around USD100 /pair) and substitute the SBs with a pair of FRs.

I have some in mind, but I don't know what would be the most suited for a xover point of around 300-500. I want to try OB on FRs first, and if it does not work (mostly sure it will not becuase of short distance to rear and side walls) I will make small sealed enclosures for them.

FF85wk. I love this driver. I have directly compared it to the other 3.

For this use i'd pick it over the much more expensive A10.2 which gets disqualified quickly because it is over 2x the budget.

dave

woof

31st January 2012 12:04 AM

My bad - missed the budget requirement.:o

GaloDourado

31st January 2012 07:53 AM

Quote:

Originally Posted by planet10
(http://www.diyaudio.com/forums/full-range/205629-help-choosing-fr-8-mltl-post2884819.html#post2884819)

FF85wk. I love this driver. I have directly compared it to the other 3.

For this use i'd pick it over the much more expensive A10.2 which gets disqualified quickly because it is over 2x the budget.

dave

I usually do not listen loud, but 15w max did not seem a lot anyway. Should I be worried about max SPL? What do you think it would be the max SPL with an xover of 300/450/600hz on OB or sealed? Steep slope is not a problem.

planet10

31st January 2012 08:06 AM

Forget about power handling spec, there is no standard and are pretty much meaningless as far as home hifi is concerned.

You are also XOing them pretty high, which takes a while lot of stress off them.

dave

GaloDourado

31st January 2012 08:39 AM

So I understand that FF85wk would be happy HPed around 300hz (or higher) LR24/48 even OB or sealed as far as xmax and distortion goes.

I'll follow your suggestion and I'll order a pair.

I'll try them first OB in it's own baffle "dome shaped" on top of the MLTL cabinet, centered about 43" above ground, CTC distance from woofer around 8". If it does not work because of short distance from adyacend walls, then small sferical sealed cabs will be made.

I will do this test anyway, but... what do you imagine the results will be going from a 2-way XOed at 1.65kz to a FAST XOed at 300kz? Will it be a step up?

Our FAST MTM with these is XOed at just over 300 hz 1st order, and plays plenty loud without strain.

4th order will really extend their power handling (likely at a loss of finesse)

dave

GaloDourado

31st January 2012 07:11 PM

Hi Dave,
can you give an idea to my last question "what do you imagine the results will be, going from a 2-way XOed at 1.65kz to a FAST XOed at 300kz? Will it be a step up?"

planet10

31st January 2012 08:30 PM

The FF85wk does highs as good as some much more expensive tweeters, has better mids than the 8", and with the XO moved low is both out of the critical range and driver separation at the XO is less than the wavelengths at the XO. Get them close enuff and the drivers are essentially co-incident